• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.3
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• pp.253-268
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• 2012

Full-mouth reconstruction of a patient using dental implants is a challenge if there is vertical and horizontal bone resorption, since this includes the gingival area and restricts the position of the implants. however, hard- and soft-tissue grafting may allow the implants to be placed into the desired position. Although it is possible to regenerate lost tissues, an alternative is to use fixed detachable prostheses that restore the function and the esthetics of the gingiva and teeth. Various material combinations including metal/acrylic, metal/ceramic, and zirconia/ceramic have been used for constructing this type of restoration. Other problems include wear, separation or fracture of the resin teeth from the metal/acrylic prosthesis, chipping or fracture of porcelain from the metal/ceramic or zirconia/ceramic prosthesis, and fracture of the framework in some free-end prostheses. With virtually unbreakable, chip-proof, life-like nature, monolithic zirconia frameworks can prospectively replace other framework materials. This clinical report describes the restoration of a patient with complete fixed detachable maxillary and mandibular prostheses made of monolithic zirconia with dental implants. The occluding surfaces were made of monolithic zirconia, to decrease the risk of chipping or fracture. The prostheses were esthetically pleasing, and no clinical complications have been reported after two years.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.4
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• pp.394-404
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• 2006

Statement of problem: A conventional 3-unit fixed partial denture design with a pontic between two retainers is the most commonly used. However in cases where the mental nerve is in close proximity to the second premolar, a cantilever design can be considered. As such, logical and scientific evidence is lacking for the number and position of implants to be placed for partially edentulous patients, and no clear-cut set of treatment principles currently exist. Purpose : The purpose of this study was to evaluate prognosis of implant-supported fixed partial dentures and to compare changes in bone level which may rise due to the different factors. Material and method : The present study examined radiographical marginal bone loss in patients treated with implant-supported fixed partial dentures (87 prostheses supported by 227 implants) and evaluated the influence of the span of the pontic, type of the opposing dentition. Clinical complications were studied using a retrospective method. Within the limitation of this study. the following result were drawn Result, 1. Seven of a total of 227 implants restored with fixed prostheses failed, resulting in a 96.9% success rate. 2. Complications encountered during recall appointments included dissolution of temporary luting agent (17 cases), porcelain fracture (8 cases), loosened screws (5 cases), gingival recession (4 cases), and gingival enlargement (1 case). 3. Marginal bone loss, 1 year after prosthesis placement, was significant(P<0.05) in the group that underwent bone grafting, however no difference in annual resorption rate was observed afterwards. 4. Marginal bono loss, 1 year post-placement, was greater in cantilever-type prostheses than in centric pontic protheses (P<0.05). 5. Marginal bone loss was more pronounced in posterior regions compared to anterior regions (P<0.05). 6. The degree of marginal bone loss was proportional to the length of the pontic (P<0.05). Conclusion: The success rate of implant-supported fixed partial dentures, including marginal bone loss, was satisfactory in the present study. Factors influencing marginal bone loss included whether bone graft was performed, location of the pontic (s), location of the surgical area in the arch pontic span. Long-term evaluation is necessary for implant-supported fixed partial dentures, as are further studies on the relationship between functional load and the number of implants to be placed.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.3
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• pp.268-274
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• 2020

Functional and esthetic recovery through reconstruction of the oral and maxillofacial system is important for patients who underwent mandibulectomy due to lesions such as oral cancer. The fibula free flap, which is frequently used in the reconstruction of the mandible, is easy to prosthetic restoration with implant placement. However, patients with growing periods have difficulty in treatment with implants when the size of the fibula is small and residual growth remains. This case is an 11-year-old female patient who underwent mandibulectomy due to osteosarcoma and reconstruction of the mandible using a fibular free flap. Functional and esthetic recovery were obtained through prosthetic restoration using implant-supported fixed prostheses. Implantation site, number of implants, and type of prostheses were considered. Implant-supported fixed prostheses were delivered at 13 years old, and after an additional 1 year observation, stable results were obtained. However, observing changes in the maxillofacial system through further examinations is necessary.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.88-96
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• 2021

Fixed implant prostheses or removable partial dentures are common treatment for partially dentulous patients. Recently, an implant-assisted removable partial denture (IARPD) has been introduced and is widely used. In the case of removable partial dentures using implant attachment and surveyed fixed prostheses, the consideration about parallelism of insertion path between implants and surveyed fixed prostheses is an important factor for success of IARPDs. In this case, she complained of discomfort while using the mandibular removable partial denture. Thus, an IARPD using implant surveyed fixed prostheses was fabricated. Thereafter, more implants were placed by a digital guide surgery to have the same insertion path as the existing surveyed fixed prostheses. Locator attachments were installed to the left and right premolar implants, and the left molar was able to obtain support of the removable partial denture with healing abutment. The clinical results were satisfactory on the aspect of aesthetic and masticatory function.

• The Journal of the Korean dental association
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• v.56 no.9
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• pp.492-502
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• 2018

Anterior maxillary teeth play an important role in determining a person's first impression and facial profile. Implant surgery in esthetic area requires more careful diagnosis, treatment planning, surgery, and prosthetic restoration than in posterior area. To avoid complications in surgery and prosthetic restoration for implants in esthetic area, accurate diagnosis and appropriate case selection become very important. If you have decided to restore the area with implant prosthesis, you have to know exactly where to place an implant. I will discuss the ideal implant position in terms of mesio-distally, apico-coronally, labio-palatally, and implant angulation. And I would like to point out the selection of fixture diameter & length for anterior implant. Finally, a clinical implant prosthesis case in maxillary central incisor will be shown. In conclusion, for superior esthetic outcome in anterior implant prostheses, we must understand the patient's anatomic condition and know our ability.

• The Journal of the Korean dental association
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• v.51 no.5
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• pp.242-249
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• 2013

The proper occlusal design is one of the most important factors for the long-term success. The purpose of this research is to investigate and define occlusal considerations to reduce failure of implant-supported fixed prostheses. The physiological movement of implants is markedly lower than that of natural teeth and they also lack in occlusal sensitivity. Proper occulsal pattern may be assigned to compensate for the biological disadvantages and occlusal contacts must be formed where the cantilever effect is minimized. Moreover, the long-term success can be assured by reducing early occulsal loading to avoid implant overloading and selecting appropriate occlusion material.

• The Journal of Advanced Prosthodontics
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• v.7 no.4
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• pp.338-342
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• 2015

PURPOSE. This retrospective study evaluated the outcome of implant-retained overdentures (IODs) after 5-19 years of clinical function. MATERIALS AND METHODS. A retrospective analysis of patient files was performed referring to 27 patients who received 36 IODs with 3 different bar designs (group A=prefabricated round bars, n=7; group B=one-piece anterior milled bars, n=20; and group C=two bilaterally placed milled bars, n=9) in the mandible (n=24) and/or in the maxilla (n=12). The analysis focused on the survival and success rates (according to Kaplan-Meier) of the implants and prostheses. Technical complication rates for each type of restoration were analyzed and compared via one-way ANOVA and the Chi-squared test. The prevalence of peri-implantitis (radiographic bone loss ${\geq}3.5mm$) was evaluated by digital analysis of panoramic radiographs taken postoperative (baseline) and after 5-19 years of clinical function (follow-up). RESULTS. The mean observational time was 7.3 years. The survival rates of the prostheses and implants were 100% and 97.7%, respectively. Technical complications occurred more frequently in group A (mean: 3.5 during observational time) than in the other two groups (B: 0.8; C: 1.0). However, this difference was not statistically significant (P=0.58). Peri-implantitis was diagnosed for 12.4% of the implants in 37% of the patients. CONCLUSION. Bar-retained IODs are an adequate treatment option for edentulous jaws. These restorations may exhibit high implant/prosthesis survival rates (>97%), and a limited incidence of technical complications after a mean observational period of >7 years. Nevertheless, peri-implantitis was identified as a frequent and serious biological complication for this type of reconstruction.

• The Journal of Advanced Prosthodontics
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• v.5 no.3
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• pp.312-318
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• 2013

PURPOSE. The aim of this study was to compare the passivity of implant superstructures by assessing the strain development around the internal tapered connection implants with strain gauges. MATERIALS AND METHODS. A polyurethane resin block in which two implants were embedded served as a measurement model. Two groups of implant restorations utilized cement-retained design and internal surface of the first group was adjusted until premature contact between the restoration and the abutment completely disappeared. In the second group, only nodules detectable to the naked eye were removed. The third group employed screw-retained design and specimens were generated by computer-aided design/computer-aided manufacturing system (n=10). Four strain gauges were fixed on the measurement model mesially and distally to the implants. The strains developed in each strain gauge were recorded during fixation of specimens. To compare the difference among groups, repeated measures 2-factor analysis was performed at a level of significance of ${\alpha}$=.05. RESULTS. The absolute strain values were measured to analyze the magnitude of strain. The mean absolute strain value ranged from 29.53 to 412.94 ${\mu}m/m$ at the different strain gauge locations. According to the result of overall comparison, the cement-retained prosthesis groups exhibited significant difference. No significant difference was detected between milled screw-retained prostheses group and cement-retained prosthesis groups. CONCLUSION. Within the limitations of the study, it was concluded that the cement-retained designs do not always exhibit lower levels of stress than screw-retained designs. The internal adjustment of a cement-retained implant restoration is essential to achieve passive fit.

• The Journal of Advanced Prosthodontics
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• v.12 no.6
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• pp.351-360
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• 2020

PURPOSE. The aim of the present study was to compare the stress distributions on the dental implants, abutments, and bone caused by different overdenture attachment types under functional chewing forces. MATERIALS AND METHODS. The 3D finite element models of the mandible, dental implants, attachment types, and prostheses were prepared. In accordance with a conventional dental implant supported overdenture design, the dental implants were positioned at the bone level in the canine teeth region bilaterally. A total of eight models using eight different attachment systems were used in this study. All the models were loaded to simulate chewing forces generated during the centric relationship (450 N), lateral movement (400 N), protrusive movement (400 N), and also in the presence of a food mass unilaterally (200 N). Stress outputs were obtained as the maximum principal stress and the equivalent von-Mises stress. RESULTS. In all attachment types, higher stress values were observed in the abutments, dental implants, and bone in the magnet attachments in different loading conditions. The highest stress values were observed among the magnet systems in the components of the Titanmagnetics model in all loading conditions (stresses were 15.4, 17.7, and 33.1 MPa on abutment, dental implant, and bone, respectively). The lowest stress value was observed in the models of Zest and O-Ring attachments. CONCLUSION. The results of the present study implied that attachment types permitting rotation and tolerating various angles created lower stresses on the bone, dental implants, and abutments.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.4
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• pp.383-396
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• 2000

Before the advent of early plastic or maxillofacial reconstructive surgery, facial features could only be replaced and mimicked by prosthetic, artificial means. Facial deformity or dysfunction, whether congenital or acquired by trauma or mutilating disease, has long been an area of constant research, development and innovation in many cultures of the world. One of the greatest contributors to the need for maxillofacial prosthetics has been physical conflict and warfare. The use of maxillofacial prostheses is not merely the replacement of a missing or disfigured aspect of the face, but the rehabilitation of that individual back into the society from which they originate. Rehabilitation includes the restoration of the person's self worth and confidence, not just physically but psychologically. In sixteenth century, Ambroise Pare, French military surgeon, first have tried many maxillofacial prosthetics for injured war soldiers with papier-mache, silver, gold and copper. According to patient's demand who lost their maxillofacial figures, maxillofacial personnel have increased and prosthetic's skill have been advanced all of the world. Over the last decade, there has been a very rapid development in technical possibilities to provide patients with facial prostheses retained by skin penetrating implants. This article will present overall history of maxillofacial prostheses and some background information on the materials used from the old world. And to overcome still many limitation of prosthetic, new minds and new ideas for technique and materials should be developed.